Provide facilities for storage and testing of sera from subhuman primates and from humans for humoral antibodies to type C RNA tumor viruses. Test human blood or sera for biologically active virus and immunoassays. Provide leukocytes enriched for various cell types. Process cell cultures for biochemical assays. Analyze nucleic acids from cell cultures. Screen fresh explants for the conditioned media. Test normal and neoplastic tissues for growth. Conduct biological tests in granulocytes.